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1/*
2 * Copyright (c) 2004, 2005 Intel Corporation. All rights reserved.
3 * Copyright (c) 2004 Topspin Corporation. All rights reserved.
4 * Copyright (c) 2004, 2005 Voltaire Corporation. All rights reserved.
5 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
6 * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
7 * Copyright (c) 2005 Network Appliance, Inc. All rights reserved.
8 *
9 * This software is available to you under a choice of one of two
10 * licenses. You may choose to be licensed under the terms of the GNU
11 * General Public License (GPL) Version 2, available from the file
12 * COPYING in the main directory of this source tree, or the
13 * OpenIB.org BSD license below:
14 *
15 * Redistribution and use in source and binary forms, with or
16 * without modification, are permitted provided that the following
17 * conditions are met:
18 *
19 * - Redistributions of source code must retain the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer.
22 *
23 * - Redistributions in binary form must reproduce the above
24 * copyright notice, this list of conditions and the following
25 * disclaimer in the documentation and/or other materials
26 * provided with the distribution.
27 *
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
29 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
31 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
32 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
33 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
34 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
35 * SOFTWARE.
36 *
37 */
38#include <linux/dma-mapping.h>
39#include <linux/err.h>
40#include <linux/idr.h>
41#include <linux/interrupt.h>
42#include <linux/rbtree.h>
43#include <linux/sched.h>
44#include <linux/spinlock.h>
45#include <linux/workqueue.h>
46#include <linux/completion.h>
47#include <linux/slab.h>
48#include <linux/module.h>
49#include <linux/sysctl.h>
50
51#include <rdma/iw_cm.h>
52#include <rdma/ib_addr.h>
53#include <rdma/iw_portmap.h>
54#include <rdma/rdma_netlink.h>
55
56#include "iwcm.h"
57
58MODULE_AUTHOR("Tom Tucker");
59MODULE_DESCRIPTION("iWARP CM");
60MODULE_LICENSE("Dual BSD/GPL");
61
62static const char * const iwcm_rej_reason_strs[] = {
63 [ECONNRESET] = "reset by remote host",
64 [ECONNREFUSED] = "refused by remote application",
65 [ETIMEDOUT] = "setup timeout",
66};
67
68const char *__attribute_const__ iwcm_reject_msg(int reason)
69{
70 size_t index;
71
72 /* iWARP uses negative errnos */
73 index = -reason;
74
75 if (index < ARRAY_SIZE(iwcm_rej_reason_strs) &&
76 iwcm_rej_reason_strs[index])
77 return iwcm_rej_reason_strs[index];
78 else
79 return "unrecognized reason";
80}
81EXPORT_SYMBOL(iwcm_reject_msg);
82
83static struct rdma_nl_cbs iwcm_nl_cb_table[RDMA_NL_IWPM_NUM_OPS] = {
84 [RDMA_NL_IWPM_REG_PID] = {.dump = iwpm_register_pid_cb},
85 [RDMA_NL_IWPM_ADD_MAPPING] = {.dump = iwpm_add_mapping_cb},
86 [RDMA_NL_IWPM_QUERY_MAPPING] = {.dump = iwpm_add_and_query_mapping_cb},
87 [RDMA_NL_IWPM_REMOTE_INFO] = {.dump = iwpm_remote_info_cb},
88 [RDMA_NL_IWPM_HANDLE_ERR] = {.dump = iwpm_mapping_error_cb},
89 [RDMA_NL_IWPM_MAPINFO] = {.dump = iwpm_mapping_info_cb},
90 [RDMA_NL_IWPM_MAPINFO_NUM] = {.dump = iwpm_ack_mapping_info_cb},
91 [RDMA_NL_IWPM_HELLO] = {.dump = iwpm_hello_cb}
92};
93
94static struct workqueue_struct *iwcm_wq;
95struct iwcm_work {
96 struct work_struct work;
97 struct iwcm_id_private *cm_id;
98 struct list_head list;
99 struct iw_cm_event event;
100 struct list_head free_list;
101};
102
103static unsigned int default_backlog = 256;
104
105static struct ctl_table_header *iwcm_ctl_table_hdr;
106static struct ctl_table iwcm_ctl_table[] = {
107 {
108 .procname = "default_backlog",
109 .data = &default_backlog,
110 .maxlen = sizeof(default_backlog),
111 .mode = 0644,
112 .proc_handler = proc_dointvec,
113 },
114};
115
116/*
117 * The following services provide a mechanism for pre-allocating iwcm_work
118 * elements. The design pre-allocates them based on the cm_id type:
119 * LISTENING IDS: Get enough elements preallocated to handle the
120 * listen backlog.
121 * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE
122 * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE
123 *
124 * Allocating them in connect and listen avoids having to deal
125 * with allocation failures on the event upcall from the provider (which
126 * is called in the interrupt context).
127 *
128 * One exception is when creating the cm_id for incoming connection requests.
129 * There are two cases:
130 * 1) in the event upcall, cm_event_handler(), for a listening cm_id. If
131 * the backlog is exceeded, then no more connection request events will
132 * be processed. cm_event_handler() returns -ENOMEM in this case. Its up
133 * to the provider to reject the connection request.
134 * 2) in the connection request workqueue handler, cm_conn_req_handler().
135 * If work elements cannot be allocated for the new connect request cm_id,
136 * then IWCM will call the provider reject method. This is ok since
137 * cm_conn_req_handler() runs in the workqueue thread context.
138 */
139
140static struct iwcm_work *get_work(struct iwcm_id_private *cm_id_priv)
141{
142 struct iwcm_work *work;
143
144 if (list_empty(&cm_id_priv->work_free_list))
145 return NULL;
146 work = list_first_entry(&cm_id_priv->work_free_list, struct iwcm_work,
147 free_list);
148 list_del_init(&work->free_list);
149 return work;
150}
151
152static void put_work(struct iwcm_work *work)
153{
154 list_add(&work->free_list, &work->cm_id->work_free_list);
155}
156
157static void dealloc_work_entries(struct iwcm_id_private *cm_id_priv)
158{
159 struct list_head *e, *tmp;
160
161 list_for_each_safe(e, tmp, &cm_id_priv->work_free_list) {
162 list_del(e);
163 kfree(list_entry(e, struct iwcm_work, free_list));
164 }
165}
166
167static int alloc_work_entries(struct iwcm_id_private *cm_id_priv, int count)
168{
169 struct iwcm_work *work;
170
171 BUG_ON(!list_empty(&cm_id_priv->work_free_list));
172 while (count--) {
173 work = kmalloc(sizeof(struct iwcm_work), GFP_KERNEL);
174 if (!work) {
175 dealloc_work_entries(cm_id_priv);
176 return -ENOMEM;
177 }
178 work->cm_id = cm_id_priv;
179 INIT_LIST_HEAD(&work->list);
180 put_work(work);
181 }
182 return 0;
183}
184
185/*
186 * Save private data from incoming connection requests to
187 * iw_cm_event, so the low level driver doesn't have to. Adjust
188 * the event ptr to point to the local copy.
189 */
190static int copy_private_data(struct iw_cm_event *event)
191{
192 void *p;
193
194 p = kmemdup(event->private_data, event->private_data_len, GFP_ATOMIC);
195 if (!p)
196 return -ENOMEM;
197 event->private_data = p;
198 return 0;
199}
200
201static void free_cm_id(struct iwcm_id_private *cm_id_priv)
202{
203 dealloc_work_entries(cm_id_priv);
204 kfree(cm_id_priv);
205}
206
207/*
208 * Release a reference on cm_id. If the last reference is being
209 * released, free the cm_id and return 'true'.
210 */
211static bool iwcm_deref_id(struct iwcm_id_private *cm_id_priv)
212{
213 if (refcount_dec_and_test(&cm_id_priv->refcount)) {
214 BUG_ON(!list_empty(&cm_id_priv->work_list));
215 free_cm_id(cm_id_priv);
216 return true;
217 }
218
219 return false;
220}
221
222static void add_ref(struct iw_cm_id *cm_id)
223{
224 struct iwcm_id_private *cm_id_priv;
225 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
226 refcount_inc(&cm_id_priv->refcount);
227}
228
229static void rem_ref(struct iw_cm_id *cm_id)
230{
231 struct iwcm_id_private *cm_id_priv;
232
233 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
234
235 (void)iwcm_deref_id(cm_id_priv);
236}
237
238static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *event);
239
240struct iw_cm_id *iw_create_cm_id(struct ib_device *device,
241 iw_cm_handler cm_handler,
242 void *context)
243{
244 struct iwcm_id_private *cm_id_priv;
245
246 cm_id_priv = kzalloc(sizeof(*cm_id_priv), GFP_KERNEL);
247 if (!cm_id_priv)
248 return ERR_PTR(-ENOMEM);
249
250 cm_id_priv->state = IW_CM_STATE_IDLE;
251 cm_id_priv->id.device = device;
252 cm_id_priv->id.cm_handler = cm_handler;
253 cm_id_priv->id.context = context;
254 cm_id_priv->id.event_handler = cm_event_handler;
255 cm_id_priv->id.add_ref = add_ref;
256 cm_id_priv->id.rem_ref = rem_ref;
257 spin_lock_init(&cm_id_priv->lock);
258 refcount_set(&cm_id_priv->refcount, 1);
259 init_waitqueue_head(&cm_id_priv->connect_wait);
260 init_completion(&cm_id_priv->destroy_comp);
261 INIT_LIST_HEAD(&cm_id_priv->work_list);
262 INIT_LIST_HEAD(&cm_id_priv->work_free_list);
263
264 return &cm_id_priv->id;
265}
266EXPORT_SYMBOL(iw_create_cm_id);
267
268
269static int iwcm_modify_qp_err(struct ib_qp *qp)
270{
271 struct ib_qp_attr qp_attr;
272
273 if (!qp)
274 return -EINVAL;
275
276 qp_attr.qp_state = IB_QPS_ERR;
277 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
278}
279
280/*
281 * This is really the RDMAC CLOSING state. It is most similar to the
282 * IB SQD QP state.
283 */
284static int iwcm_modify_qp_sqd(struct ib_qp *qp)
285{
286 struct ib_qp_attr qp_attr;
287
288 BUG_ON(qp == NULL);
289 qp_attr.qp_state = IB_QPS_SQD;
290 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
291}
292
293/*
294 * CM_ID <-- CLOSING
295 *
296 * Block if a passive or active connection is currently being processed. Then
297 * process the event as follows:
298 * - If we are ESTABLISHED, move to CLOSING and modify the QP state
299 * based on the abrupt flag
300 * - If the connection is already in the CLOSING or IDLE state, the peer is
301 * disconnecting concurrently with us and we've already seen the
302 * DISCONNECT event -- ignore the request and return 0
303 * - Disconnect on a listening endpoint returns -EINVAL
304 */
305int iw_cm_disconnect(struct iw_cm_id *cm_id, int abrupt)
306{
307 struct iwcm_id_private *cm_id_priv;
308 unsigned long flags;
309 int ret = 0;
310 struct ib_qp *qp = NULL;
311
312 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
313 /* Wait if we're currently in a connect or accept downcall */
314 wait_event(cm_id_priv->connect_wait,
315 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
316
317 spin_lock_irqsave(&cm_id_priv->lock, flags);
318 switch (cm_id_priv->state) {
319 case IW_CM_STATE_ESTABLISHED:
320 cm_id_priv->state = IW_CM_STATE_CLOSING;
321
322 /* QP could be <nul> for user-mode client */
323 if (cm_id_priv->qp)
324 qp = cm_id_priv->qp;
325 else
326 ret = -EINVAL;
327 break;
328 case IW_CM_STATE_LISTEN:
329 ret = -EINVAL;
330 break;
331 case IW_CM_STATE_CLOSING:
332 /* remote peer closed first */
333 case IW_CM_STATE_IDLE:
334 /* accept or connect returned !0 */
335 break;
336 case IW_CM_STATE_CONN_RECV:
337 /*
338 * App called disconnect before/without calling accept after
339 * connect_request event delivered.
340 */
341 break;
342 case IW_CM_STATE_CONN_SENT:
343 /* Can only get here if wait above fails */
344 default:
345 BUG();
346 }
347 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
348
349 if (qp) {
350 if (abrupt)
351 ret = iwcm_modify_qp_err(qp);
352 else
353 ret = iwcm_modify_qp_sqd(qp);
354
355 /*
356 * If both sides are disconnecting the QP could
357 * already be in ERR or SQD states
358 */
359 ret = 0;
360 }
361
362 return ret;
363}
364EXPORT_SYMBOL(iw_cm_disconnect);
365
366/*
367 * CM_ID <-- DESTROYING
368 *
369 * Clean up all resources associated with the connection and release
370 * the initial reference taken by iw_create_cm_id.
371 *
372 * Returns true if and only if the last cm_id_priv reference has been dropped.
373 */
374static bool destroy_cm_id(struct iw_cm_id *cm_id)
375{
376 struct iwcm_id_private *cm_id_priv;
377 struct ib_qp *qp;
378 unsigned long flags;
379
380 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
381 /*
382 * Wait if we're currently in a connect or accept downcall. A
383 * listening endpoint should never block here.
384 */
385 wait_event(cm_id_priv->connect_wait,
386 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
387
388 /*
389 * Since we're deleting the cm_id, drop any events that
390 * might arrive before the last dereference.
391 */
392 set_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags);
393
394 spin_lock_irqsave(&cm_id_priv->lock, flags);
395 qp = cm_id_priv->qp;
396 cm_id_priv->qp = NULL;
397
398 switch (cm_id_priv->state) {
399 case IW_CM_STATE_LISTEN:
400 cm_id_priv->state = IW_CM_STATE_DESTROYING;
401 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
402 /* destroy the listening endpoint */
403 cm_id->device->ops.iw_destroy_listen(cm_id);
404 spin_lock_irqsave(&cm_id_priv->lock, flags);
405 break;
406 case IW_CM_STATE_ESTABLISHED:
407 cm_id_priv->state = IW_CM_STATE_DESTROYING;
408 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
409 /* Abrupt close of the connection */
410 (void)iwcm_modify_qp_err(qp);
411 spin_lock_irqsave(&cm_id_priv->lock, flags);
412 break;
413 case IW_CM_STATE_IDLE:
414 case IW_CM_STATE_CLOSING:
415 cm_id_priv->state = IW_CM_STATE_DESTROYING;
416 break;
417 case IW_CM_STATE_CONN_RECV:
418 /*
419 * App called destroy before/without calling accept after
420 * receiving connection request event notification or
421 * returned non zero from the event callback function.
422 * In either case, must tell the provider to reject.
423 */
424 cm_id_priv->state = IW_CM_STATE_DESTROYING;
425 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
426 cm_id->device->ops.iw_reject(cm_id, NULL, 0);
427 spin_lock_irqsave(&cm_id_priv->lock, flags);
428 break;
429 case IW_CM_STATE_CONN_SENT:
430 case IW_CM_STATE_DESTROYING:
431 default:
432 BUG();
433 break;
434 }
435 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
436 if (qp)
437 cm_id_priv->id.device->ops.iw_rem_ref(qp);
438
439 if (cm_id->mapped) {
440 iwpm_remove_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr);
441 iwpm_remove_mapping(&cm_id->local_addr, RDMA_NL_IWCM);
442 }
443
444 return iwcm_deref_id(cm_id_priv);
445}
446
447/*
448 * This function is only called by the application thread and cannot
449 * be called by the event thread. The function will wait for all
450 * references to be released on the cm_id and then kfree the cm_id
451 * object.
452 */
453void iw_destroy_cm_id(struct iw_cm_id *cm_id)
454{
455 if (!destroy_cm_id(cm_id))
456 flush_workqueue(iwcm_wq);
457}
458EXPORT_SYMBOL(iw_destroy_cm_id);
459
460/**
461 * iw_cm_check_wildcard - If IP address is 0 then use original
462 * @pm_addr: sockaddr containing the ip to check for wildcard
463 * @cm_addr: sockaddr containing the actual IP address
464 * @cm_outaddr: sockaddr to set IP addr which leaving port
465 *
466 * Checks the pm_addr for wildcard and then sets cm_outaddr's
467 * IP to the actual (cm_addr).
468 */
469static void iw_cm_check_wildcard(struct sockaddr_storage *pm_addr,
470 struct sockaddr_storage *cm_addr,
471 struct sockaddr_storage *cm_outaddr)
472{
473 if (pm_addr->ss_family == AF_INET) {
474 struct sockaddr_in *pm4_addr = (struct sockaddr_in *)pm_addr;
475
476 if (pm4_addr->sin_addr.s_addr == htonl(INADDR_ANY)) {
477 struct sockaddr_in *cm4_addr =
478 (struct sockaddr_in *)cm_addr;
479 struct sockaddr_in *cm4_outaddr =
480 (struct sockaddr_in *)cm_outaddr;
481
482 cm4_outaddr->sin_addr = cm4_addr->sin_addr;
483 }
484 } else {
485 struct sockaddr_in6 *pm6_addr = (struct sockaddr_in6 *)pm_addr;
486
487 if (ipv6_addr_type(&pm6_addr->sin6_addr) == IPV6_ADDR_ANY) {
488 struct sockaddr_in6 *cm6_addr =
489 (struct sockaddr_in6 *)cm_addr;
490 struct sockaddr_in6 *cm6_outaddr =
491 (struct sockaddr_in6 *)cm_outaddr;
492
493 cm6_outaddr->sin6_addr = cm6_addr->sin6_addr;
494 }
495 }
496}
497
498/**
499 * iw_cm_map - Use portmapper to map the ports
500 * @cm_id: connection manager pointer
501 * @active: Indicates the active side when true
502 * returns nonzero for error only if iwpm_create_mapinfo() fails
503 *
504 * Tries to add a mapping for a port using the Portmapper. If
505 * successful in mapping the IP/Port it will check the remote
506 * mapped IP address for a wildcard IP address and replace the
507 * zero IP address with the remote_addr.
508 */
509static int iw_cm_map(struct iw_cm_id *cm_id, bool active)
510{
511 const char *devname = dev_name(&cm_id->device->dev);
512 const char *ifname = cm_id->device->iw_ifname;
513 struct iwpm_dev_data pm_reg_msg = {};
514 struct iwpm_sa_data pm_msg;
515 int status;
516
517 if (strlen(devname) >= sizeof(pm_reg_msg.dev_name) ||
518 strlen(ifname) >= sizeof(pm_reg_msg.if_name))
519 return -EINVAL;
520
521 cm_id->m_local_addr = cm_id->local_addr;
522 cm_id->m_remote_addr = cm_id->remote_addr;
523
524 strcpy(pm_reg_msg.dev_name, devname);
525 strcpy(pm_reg_msg.if_name, ifname);
526
527 if (iwpm_register_pid(&pm_reg_msg, RDMA_NL_IWCM) ||
528 !iwpm_valid_pid())
529 return 0;
530
531 cm_id->mapped = true;
532 pm_msg.loc_addr = cm_id->local_addr;
533 pm_msg.rem_addr = cm_id->remote_addr;
534 pm_msg.flags = (cm_id->device->iw_driver_flags & IW_F_NO_PORT_MAP) ?
535 IWPM_FLAGS_NO_PORT_MAP : 0;
536 if (active)
537 status = iwpm_add_and_query_mapping(&pm_msg,
538 RDMA_NL_IWCM);
539 else
540 status = iwpm_add_mapping(&pm_msg, RDMA_NL_IWCM);
541
542 if (!status) {
543 cm_id->m_local_addr = pm_msg.mapped_loc_addr;
544 if (active) {
545 cm_id->m_remote_addr = pm_msg.mapped_rem_addr;
546 iw_cm_check_wildcard(&pm_msg.mapped_rem_addr,
547 &cm_id->remote_addr,
548 &cm_id->m_remote_addr);
549 }
550 }
551
552 return iwpm_create_mapinfo(&cm_id->local_addr,
553 &cm_id->m_local_addr,
554 RDMA_NL_IWCM, pm_msg.flags);
555}
556
557/*
558 * CM_ID <-- LISTEN
559 *
560 * Start listening for connect requests. Generates one CONNECT_REQUEST
561 * event for each inbound connect request.
562 */
563int iw_cm_listen(struct iw_cm_id *cm_id, int backlog)
564{
565 struct iwcm_id_private *cm_id_priv;
566 unsigned long flags;
567 int ret;
568
569 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
570
571 if (!backlog)
572 backlog = default_backlog;
573
574 ret = alloc_work_entries(cm_id_priv, backlog);
575 if (ret)
576 return ret;
577
578 spin_lock_irqsave(&cm_id_priv->lock, flags);
579 switch (cm_id_priv->state) {
580 case IW_CM_STATE_IDLE:
581 cm_id_priv->state = IW_CM_STATE_LISTEN;
582 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
583 ret = iw_cm_map(cm_id, false);
584 if (!ret)
585 ret = cm_id->device->ops.iw_create_listen(cm_id,
586 backlog);
587 if (ret)
588 cm_id_priv->state = IW_CM_STATE_IDLE;
589 spin_lock_irqsave(&cm_id_priv->lock, flags);
590 break;
591 default:
592 ret = -EINVAL;
593 }
594 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
595
596 return ret;
597}
598EXPORT_SYMBOL(iw_cm_listen);
599
600/*
601 * CM_ID <-- IDLE
602 *
603 * Rejects an inbound connection request. No events are generated.
604 */
605int iw_cm_reject(struct iw_cm_id *cm_id,
606 const void *private_data,
607 u8 private_data_len)
608{
609 struct iwcm_id_private *cm_id_priv;
610 unsigned long flags;
611 int ret;
612
613 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
614 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
615
616 spin_lock_irqsave(&cm_id_priv->lock, flags);
617 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
618 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
619 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
620 wake_up_all(&cm_id_priv->connect_wait);
621 return -EINVAL;
622 }
623 cm_id_priv->state = IW_CM_STATE_IDLE;
624 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
625
626 ret = cm_id->device->ops.iw_reject(cm_id, private_data,
627 private_data_len);
628
629 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
630 wake_up_all(&cm_id_priv->connect_wait);
631
632 return ret;
633}
634EXPORT_SYMBOL(iw_cm_reject);
635
636/*
637 * CM_ID <-- ESTABLISHED
638 *
639 * Accepts an inbound connection request and generates an ESTABLISHED
640 * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block
641 * until the ESTABLISHED event is received from the provider.
642 */
643int iw_cm_accept(struct iw_cm_id *cm_id,
644 struct iw_cm_conn_param *iw_param)
645{
646 struct iwcm_id_private *cm_id_priv;
647 struct ib_qp *qp;
648 unsigned long flags;
649 int ret;
650
651 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
652 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
653
654 spin_lock_irqsave(&cm_id_priv->lock, flags);
655 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
656 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
657 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
658 wake_up_all(&cm_id_priv->connect_wait);
659 return -EINVAL;
660 }
661 /* Get the ib_qp given the QPN */
662 qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn);
663 if (!qp) {
664 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
665 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
666 wake_up_all(&cm_id_priv->connect_wait);
667 return -EINVAL;
668 }
669 cm_id->device->ops.iw_add_ref(qp);
670 cm_id_priv->qp = qp;
671 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
672
673 ret = cm_id->device->ops.iw_accept(cm_id, iw_param);
674 if (ret) {
675 /* An error on accept precludes provider events */
676 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
677 cm_id_priv->state = IW_CM_STATE_IDLE;
678 spin_lock_irqsave(&cm_id_priv->lock, flags);
679 qp = cm_id_priv->qp;
680 cm_id_priv->qp = NULL;
681 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
682 if (qp)
683 cm_id->device->ops.iw_rem_ref(qp);
684 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
685 wake_up_all(&cm_id_priv->connect_wait);
686 }
687
688 return ret;
689}
690EXPORT_SYMBOL(iw_cm_accept);
691
692/*
693 * Active Side: CM_ID <-- CONN_SENT
694 *
695 * If successful, results in the generation of a CONNECT_REPLY
696 * event. iw_cm_disconnect and iw_cm_destroy will block until the
697 * CONNECT_REPLY event is received from the provider.
698 */
699int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param)
700{
701 struct iwcm_id_private *cm_id_priv;
702 int ret;
703 unsigned long flags;
704 struct ib_qp *qp = NULL;
705
706 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
707
708 ret = alloc_work_entries(cm_id_priv, 4);
709 if (ret)
710 return ret;
711
712 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
713 spin_lock_irqsave(&cm_id_priv->lock, flags);
714
715 if (cm_id_priv->state != IW_CM_STATE_IDLE) {
716 ret = -EINVAL;
717 goto err;
718 }
719
720 /* Get the ib_qp given the QPN */
721 qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn);
722 if (!qp) {
723 ret = -EINVAL;
724 goto err;
725 }
726 cm_id->device->ops.iw_add_ref(qp);
727 cm_id_priv->qp = qp;
728 cm_id_priv->state = IW_CM_STATE_CONN_SENT;
729 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
730
731 ret = iw_cm_map(cm_id, true);
732 if (!ret)
733 ret = cm_id->device->ops.iw_connect(cm_id, iw_param);
734 if (!ret)
735 return 0; /* success */
736
737 spin_lock_irqsave(&cm_id_priv->lock, flags);
738 qp = cm_id_priv->qp;
739 cm_id_priv->qp = NULL;
740 cm_id_priv->state = IW_CM_STATE_IDLE;
741err:
742 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
743 if (qp)
744 cm_id->device->ops.iw_rem_ref(qp);
745 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
746 wake_up_all(&cm_id_priv->connect_wait);
747 return ret;
748}
749EXPORT_SYMBOL(iw_cm_connect);
750
751/*
752 * Passive Side: new CM_ID <-- CONN_RECV
753 *
754 * Handles an inbound connect request. The function creates a new
755 * iw_cm_id to represent the new connection and inherits the client
756 * callback function and other attributes from the listening parent.
757 *
758 * The work item contains a pointer to the listen_cm_id and the event. The
759 * listen_cm_id contains the client cm_handler, context and
760 * device. These are copied when the device is cloned. The event
761 * contains the new four tuple.
762 *
763 * An error on the child should not affect the parent, so this
764 * function does not return a value.
765 */
766static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv,
767 struct iw_cm_event *iw_event)
768{
769 unsigned long flags;
770 struct iw_cm_id *cm_id;
771 struct iwcm_id_private *cm_id_priv;
772 int ret;
773
774 /*
775 * The provider should never generate a connection request
776 * event with a bad status.
777 */
778 BUG_ON(iw_event->status);
779
780 cm_id = iw_create_cm_id(listen_id_priv->id.device,
781 listen_id_priv->id.cm_handler,
782 listen_id_priv->id.context);
783 /* If the cm_id could not be created, ignore the request */
784 if (IS_ERR(cm_id))
785 goto out;
786
787 cm_id->provider_data = iw_event->provider_data;
788 cm_id->m_local_addr = iw_event->local_addr;
789 cm_id->m_remote_addr = iw_event->remote_addr;
790 cm_id->local_addr = listen_id_priv->id.local_addr;
791
792 ret = iwpm_get_remote_info(&listen_id_priv->id.m_local_addr,
793 &iw_event->remote_addr,
794 &cm_id->remote_addr,
795 RDMA_NL_IWCM);
796 if (ret) {
797 cm_id->remote_addr = iw_event->remote_addr;
798 } else {
799 iw_cm_check_wildcard(&listen_id_priv->id.m_local_addr,
800 &iw_event->local_addr,
801 &cm_id->local_addr);
802 iw_event->local_addr = cm_id->local_addr;
803 iw_event->remote_addr = cm_id->remote_addr;
804 }
805
806 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
807 cm_id_priv->state = IW_CM_STATE_CONN_RECV;
808
809 /*
810 * We could be destroying the listening id. If so, ignore this
811 * upcall.
812 */
813 spin_lock_irqsave(&listen_id_priv->lock, flags);
814 if (listen_id_priv->state != IW_CM_STATE_LISTEN) {
815 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
816 iw_cm_reject(cm_id, NULL, 0);
817 iw_destroy_cm_id(cm_id);
818 goto out;
819 }
820 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
821
822 ret = alloc_work_entries(cm_id_priv, 3);
823 if (ret) {
824 iw_cm_reject(cm_id, NULL, 0);
825 iw_destroy_cm_id(cm_id);
826 goto out;
827 }
828
829 /* Call the client CM handler */
830 ret = cm_id->cm_handler(cm_id, iw_event);
831 if (ret) {
832 iw_cm_reject(cm_id, NULL, 0);
833 iw_destroy_cm_id(cm_id);
834 }
835
836out:
837 if (iw_event->private_data_len)
838 kfree(iw_event->private_data);
839}
840
841/*
842 * Passive Side: CM_ID <-- ESTABLISHED
843 *
844 * The provider generated an ESTABLISHED event which means that
845 * the MPA negotion has completed successfully and we are now in MPA
846 * FPDU mode.
847 *
848 * This event can only be received in the CONN_RECV state. If the
849 * remote peer closed, the ESTABLISHED event would be received followed
850 * by the CLOSE event. If the app closes, it will block until we wake
851 * it up after processing this event.
852 */
853static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv,
854 struct iw_cm_event *iw_event)
855{
856 unsigned long flags;
857 int ret;
858
859 spin_lock_irqsave(&cm_id_priv->lock, flags);
860
861 /*
862 * We clear the CONNECT_WAIT bit here to allow the callback
863 * function to call iw_cm_disconnect. Calling iw_destroy_cm_id
864 * from a callback handler is not allowed.
865 */
866 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
867 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
868 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
869 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
870 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
871 wake_up_all(&cm_id_priv->connect_wait);
872
873 return ret;
874}
875
876/*
877 * Active Side: CM_ID <-- ESTABLISHED
878 *
879 * The app has called connect and is waiting for the established event to
880 * post it's requests to the server. This event will wake up anyone
881 * blocked in iw_cm_disconnect or iw_destroy_id.
882 */
883static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv,
884 struct iw_cm_event *iw_event)
885{
886 struct ib_qp *qp = NULL;
887 unsigned long flags;
888 int ret;
889
890 spin_lock_irqsave(&cm_id_priv->lock, flags);
891 /*
892 * Clear the connect wait bit so a callback function calling
893 * iw_cm_disconnect will not wait and deadlock this thread
894 */
895 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
896 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT);
897 if (iw_event->status == 0) {
898 cm_id_priv->id.m_local_addr = iw_event->local_addr;
899 cm_id_priv->id.m_remote_addr = iw_event->remote_addr;
900 iw_event->local_addr = cm_id_priv->id.local_addr;
901 iw_event->remote_addr = cm_id_priv->id.remote_addr;
902 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
903 } else {
904 /* REJECTED or RESET */
905 qp = cm_id_priv->qp;
906 cm_id_priv->qp = NULL;
907 cm_id_priv->state = IW_CM_STATE_IDLE;
908 }
909 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
910 if (qp)
911 cm_id_priv->id.device->ops.iw_rem_ref(qp);
912 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
913
914 if (iw_event->private_data_len)
915 kfree(iw_event->private_data);
916
917 /* Wake up waiters on connect complete */
918 wake_up_all(&cm_id_priv->connect_wait);
919
920 return ret;
921}
922
923/*
924 * CM_ID <-- CLOSING
925 *
926 * If in the ESTABLISHED state, move to CLOSING.
927 */
928static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv,
929 struct iw_cm_event *iw_event)
930{
931 unsigned long flags;
932
933 spin_lock_irqsave(&cm_id_priv->lock, flags);
934 if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED)
935 cm_id_priv->state = IW_CM_STATE_CLOSING;
936 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
937}
938
939/*
940 * CM_ID <-- IDLE
941 *
942 * If in the ESTBLISHED or CLOSING states, the QP will have have been
943 * moved by the provider to the ERR state. Disassociate the CM_ID from
944 * the QP, move to IDLE, and remove the 'connected' reference.
945 *
946 * If in some other state, the cm_id was destroyed asynchronously.
947 * This is the last reference that will result in waking up
948 * the app thread blocked in iw_destroy_cm_id.
949 */
950static int cm_close_handler(struct iwcm_id_private *cm_id_priv,
951 struct iw_cm_event *iw_event)
952{
953 struct ib_qp *qp;
954 unsigned long flags;
955 int ret = 0, notify_event = 0;
956 spin_lock_irqsave(&cm_id_priv->lock, flags);
957 qp = cm_id_priv->qp;
958 cm_id_priv->qp = NULL;
959
960 switch (cm_id_priv->state) {
961 case IW_CM_STATE_ESTABLISHED:
962 case IW_CM_STATE_CLOSING:
963 cm_id_priv->state = IW_CM_STATE_IDLE;
964 notify_event = 1;
965 break;
966 case IW_CM_STATE_DESTROYING:
967 break;
968 default:
969 BUG();
970 }
971 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
972
973 if (qp)
974 cm_id_priv->id.device->ops.iw_rem_ref(qp);
975 if (notify_event)
976 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
977 return ret;
978}
979
980static int process_event(struct iwcm_id_private *cm_id_priv,
981 struct iw_cm_event *iw_event)
982{
983 int ret = 0;
984
985 switch (iw_event->event) {
986 case IW_CM_EVENT_CONNECT_REQUEST:
987 cm_conn_req_handler(cm_id_priv, iw_event);
988 break;
989 case IW_CM_EVENT_CONNECT_REPLY:
990 ret = cm_conn_rep_handler(cm_id_priv, iw_event);
991 break;
992 case IW_CM_EVENT_ESTABLISHED:
993 ret = cm_conn_est_handler(cm_id_priv, iw_event);
994 break;
995 case IW_CM_EVENT_DISCONNECT:
996 cm_disconnect_handler(cm_id_priv, iw_event);
997 break;
998 case IW_CM_EVENT_CLOSE:
999 ret = cm_close_handler(cm_id_priv, iw_event);
1000 break;
1001 default:
1002 BUG();
1003 }
1004
1005 return ret;
1006}
1007
1008/*
1009 * Process events on the work_list for the cm_id. If the callback
1010 * function requests that the cm_id be deleted, a flag is set in the
1011 * cm_id flags to indicate that when the last reference is
1012 * removed, the cm_id is to be destroyed. This is necessary to
1013 * distinguish between an object that will be destroyed by the app
1014 * thread asleep on the destroy_comp list vs. an object destroyed
1015 * here synchronously when the last reference is removed.
1016 */
1017static void cm_work_handler(struct work_struct *_work)
1018{
1019 struct iwcm_work *work = container_of(_work, struct iwcm_work, work);
1020 struct iw_cm_event levent;
1021 struct iwcm_id_private *cm_id_priv = work->cm_id;
1022 unsigned long flags;
1023 int ret = 0;
1024
1025 spin_lock_irqsave(&cm_id_priv->lock, flags);
1026 while (!list_empty(&cm_id_priv->work_list)) {
1027 work = list_first_entry(&cm_id_priv->work_list,
1028 struct iwcm_work, list);
1029 list_del_init(&work->list);
1030 levent = work->event;
1031 put_work(work);
1032 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1033
1034 if (!test_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags)) {
1035 ret = process_event(cm_id_priv, &levent);
1036 if (ret)
1037 WARN_ON_ONCE(destroy_cm_id(&cm_id_priv->id));
1038 } else
1039 pr_debug("dropping event %d\n", levent.event);
1040 if (iwcm_deref_id(cm_id_priv))
1041 return;
1042 spin_lock_irqsave(&cm_id_priv->lock, flags);
1043 }
1044 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1045}
1046
1047/*
1048 * This function is called on interrupt context. Schedule events on
1049 * the iwcm_wq thread to allow callback functions to downcall into
1050 * the CM and/or block. Events are queued to a per-CM_ID
1051 * work_list. If this is the first event on the work_list, the work
1052 * element is also queued on the iwcm_wq thread.
1053 *
1054 * Each event holds a reference on the cm_id. Until the last posted
1055 * event has been delivered and processed, the cm_id cannot be
1056 * deleted.
1057 *
1058 * Returns:
1059 * 0 - the event was handled.
1060 * -ENOMEM - the event was not handled due to lack of resources.
1061 */
1062static int cm_event_handler(struct iw_cm_id *cm_id,
1063 struct iw_cm_event *iw_event)
1064{
1065 struct iwcm_work *work;
1066 struct iwcm_id_private *cm_id_priv;
1067 unsigned long flags;
1068 int ret = 0;
1069
1070 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
1071
1072 spin_lock_irqsave(&cm_id_priv->lock, flags);
1073 work = get_work(cm_id_priv);
1074 if (!work) {
1075 ret = -ENOMEM;
1076 goto out;
1077 }
1078
1079 INIT_WORK(&work->work, cm_work_handler);
1080 work->cm_id = cm_id_priv;
1081 work->event = *iw_event;
1082
1083 if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST ||
1084 work->event.event == IW_CM_EVENT_CONNECT_REPLY) &&
1085 work->event.private_data_len) {
1086 ret = copy_private_data(&work->event);
1087 if (ret) {
1088 put_work(work);
1089 goto out;
1090 }
1091 }
1092
1093 refcount_inc(&cm_id_priv->refcount);
1094 list_add_tail(&work->list, &cm_id_priv->work_list);
1095 queue_work(iwcm_wq, &work->work);
1096out:
1097 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1098 return ret;
1099}
1100
1101static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv,
1102 struct ib_qp_attr *qp_attr,
1103 int *qp_attr_mask)
1104{
1105 unsigned long flags;
1106 int ret;
1107
1108 spin_lock_irqsave(&cm_id_priv->lock, flags);
1109 switch (cm_id_priv->state) {
1110 case IW_CM_STATE_IDLE:
1111 case IW_CM_STATE_CONN_SENT:
1112 case IW_CM_STATE_CONN_RECV:
1113 case IW_CM_STATE_ESTABLISHED:
1114 *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS;
1115 qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE|
1116 IB_ACCESS_REMOTE_READ;
1117 ret = 0;
1118 break;
1119 default:
1120 ret = -EINVAL;
1121 break;
1122 }
1123 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1124 return ret;
1125}
1126
1127static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv,
1128 struct ib_qp_attr *qp_attr,
1129 int *qp_attr_mask)
1130{
1131 unsigned long flags;
1132 int ret;
1133
1134 spin_lock_irqsave(&cm_id_priv->lock, flags);
1135 switch (cm_id_priv->state) {
1136 case IW_CM_STATE_IDLE:
1137 case IW_CM_STATE_CONN_SENT:
1138 case IW_CM_STATE_CONN_RECV:
1139 case IW_CM_STATE_ESTABLISHED:
1140 *qp_attr_mask = 0;
1141 ret = 0;
1142 break;
1143 default:
1144 ret = -EINVAL;
1145 break;
1146 }
1147 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1148 return ret;
1149}
1150
1151int iw_cm_init_qp_attr(struct iw_cm_id *cm_id,
1152 struct ib_qp_attr *qp_attr,
1153 int *qp_attr_mask)
1154{
1155 struct iwcm_id_private *cm_id_priv;
1156 int ret;
1157
1158 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
1159 switch (qp_attr->qp_state) {
1160 case IB_QPS_INIT:
1161 case IB_QPS_RTR:
1162 ret = iwcm_init_qp_init_attr(cm_id_priv,
1163 qp_attr, qp_attr_mask);
1164 break;
1165 case IB_QPS_RTS:
1166 ret = iwcm_init_qp_rts_attr(cm_id_priv,
1167 qp_attr, qp_attr_mask);
1168 break;
1169 default:
1170 ret = -EINVAL;
1171 break;
1172 }
1173 return ret;
1174}
1175EXPORT_SYMBOL(iw_cm_init_qp_attr);
1176
1177static int __init iw_cm_init(void)
1178{
1179 int ret;
1180
1181 ret = iwpm_init(RDMA_NL_IWCM);
1182 if (ret)
1183 return ret;
1184
1185 iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", WQ_MEM_RECLAIM);
1186 if (!iwcm_wq)
1187 goto err_alloc;
1188
1189 iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm",
1190 iwcm_ctl_table);
1191 if (!iwcm_ctl_table_hdr) {
1192 pr_err("iw_cm: couldn't register sysctl paths\n");
1193 goto err_sysctl;
1194 }
1195
1196 rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table);
1197 return 0;
1198
1199err_sysctl:
1200 destroy_workqueue(iwcm_wq);
1201err_alloc:
1202 iwpm_exit(RDMA_NL_IWCM);
1203 return -ENOMEM;
1204}
1205
1206static void __exit iw_cm_cleanup(void)
1207{
1208 rdma_nl_unregister(RDMA_NL_IWCM);
1209 unregister_net_sysctl_table(iwcm_ctl_table_hdr);
1210 destroy_workqueue(iwcm_wq);
1211 iwpm_exit(RDMA_NL_IWCM);
1212}
1213
1214MODULE_ALIAS_RDMA_NETLINK(RDMA_NL_IWCM, 2);
1215
1216module_init(iw_cm_init);
1217module_exit(iw_cm_cleanup);
1/*
2 * Copyright (c) 2004, 2005 Intel Corporation. All rights reserved.
3 * Copyright (c) 2004 Topspin Corporation. All rights reserved.
4 * Copyright (c) 2004, 2005 Voltaire Corporation. All rights reserved.
5 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
6 * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
7 * Copyright (c) 2005 Network Appliance, Inc. All rights reserved.
8 *
9 * This software is available to you under a choice of one of two
10 * licenses. You may choose to be licensed under the terms of the GNU
11 * General Public License (GPL) Version 2, available from the file
12 * COPYING in the main directory of this source tree, or the
13 * OpenIB.org BSD license below:
14 *
15 * Redistribution and use in source and binary forms, with or
16 * without modification, are permitted provided that the following
17 * conditions are met:
18 *
19 * - Redistributions of source code must retain the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer.
22 *
23 * - Redistributions in binary form must reproduce the above
24 * copyright notice, this list of conditions and the following
25 * disclaimer in the documentation and/or other materials
26 * provided with the distribution.
27 *
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
29 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
31 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
32 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
33 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
34 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
35 * SOFTWARE.
36 *
37 */
38#include <linux/dma-mapping.h>
39#include <linux/err.h>
40#include <linux/idr.h>
41#include <linux/interrupt.h>
42#include <linux/rbtree.h>
43#include <linux/sched.h>
44#include <linux/spinlock.h>
45#include <linux/workqueue.h>
46#include <linux/completion.h>
47#include <linux/slab.h>
48#include <linux/module.h>
49#include <linux/sysctl.h>
50
51#include <rdma/iw_cm.h>
52#include <rdma/ib_addr.h>
53#include <rdma/iw_portmap.h>
54#include <rdma/rdma_netlink.h>
55
56#include "iwcm.h"
57
58MODULE_AUTHOR("Tom Tucker");
59MODULE_DESCRIPTION("iWARP CM");
60MODULE_LICENSE("Dual BSD/GPL");
61
62static struct ibnl_client_cbs iwcm_nl_cb_table[] = {
63 [RDMA_NL_IWPM_REG_PID] = {.dump = iwpm_register_pid_cb},
64 [RDMA_NL_IWPM_ADD_MAPPING] = {.dump = iwpm_add_mapping_cb},
65 [RDMA_NL_IWPM_QUERY_MAPPING] = {.dump = iwpm_add_and_query_mapping_cb},
66 [RDMA_NL_IWPM_REMOTE_INFO] = {.dump = iwpm_remote_info_cb},
67 [RDMA_NL_IWPM_HANDLE_ERR] = {.dump = iwpm_mapping_error_cb},
68 [RDMA_NL_IWPM_MAPINFO] = {.dump = iwpm_mapping_info_cb},
69 [RDMA_NL_IWPM_MAPINFO_NUM] = {.dump = iwpm_ack_mapping_info_cb}
70};
71
72static struct workqueue_struct *iwcm_wq;
73struct iwcm_work {
74 struct work_struct work;
75 struct iwcm_id_private *cm_id;
76 struct list_head list;
77 struct iw_cm_event event;
78 struct list_head free_list;
79};
80
81static unsigned int default_backlog = 256;
82
83static struct ctl_table_header *iwcm_ctl_table_hdr;
84static struct ctl_table iwcm_ctl_table[] = {
85 {
86 .procname = "default_backlog",
87 .data = &default_backlog,
88 .maxlen = sizeof(default_backlog),
89 .mode = 0644,
90 .proc_handler = proc_dointvec,
91 },
92 { }
93};
94
95/*
96 * The following services provide a mechanism for pre-allocating iwcm_work
97 * elements. The design pre-allocates them based on the cm_id type:
98 * LISTENING IDS: Get enough elements preallocated to handle the
99 * listen backlog.
100 * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE
101 * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE
102 *
103 * Allocating them in connect and listen avoids having to deal
104 * with allocation failures on the event upcall from the provider (which
105 * is called in the interrupt context).
106 *
107 * One exception is when creating the cm_id for incoming connection requests.
108 * There are two cases:
109 * 1) in the event upcall, cm_event_handler(), for a listening cm_id. If
110 * the backlog is exceeded, then no more connection request events will
111 * be processed. cm_event_handler() returns -ENOMEM in this case. Its up
112 * to the provider to reject the connection request.
113 * 2) in the connection request workqueue handler, cm_conn_req_handler().
114 * If work elements cannot be allocated for the new connect request cm_id,
115 * then IWCM will call the provider reject method. This is ok since
116 * cm_conn_req_handler() runs in the workqueue thread context.
117 */
118
119static struct iwcm_work *get_work(struct iwcm_id_private *cm_id_priv)
120{
121 struct iwcm_work *work;
122
123 if (list_empty(&cm_id_priv->work_free_list))
124 return NULL;
125 work = list_entry(cm_id_priv->work_free_list.next, struct iwcm_work,
126 free_list);
127 list_del_init(&work->free_list);
128 return work;
129}
130
131static void put_work(struct iwcm_work *work)
132{
133 list_add(&work->free_list, &work->cm_id->work_free_list);
134}
135
136static void dealloc_work_entries(struct iwcm_id_private *cm_id_priv)
137{
138 struct list_head *e, *tmp;
139
140 list_for_each_safe(e, tmp, &cm_id_priv->work_free_list)
141 kfree(list_entry(e, struct iwcm_work, free_list));
142}
143
144static int alloc_work_entries(struct iwcm_id_private *cm_id_priv, int count)
145{
146 struct iwcm_work *work;
147
148 BUG_ON(!list_empty(&cm_id_priv->work_free_list));
149 while (count--) {
150 work = kmalloc(sizeof(struct iwcm_work), GFP_KERNEL);
151 if (!work) {
152 dealloc_work_entries(cm_id_priv);
153 return -ENOMEM;
154 }
155 work->cm_id = cm_id_priv;
156 INIT_LIST_HEAD(&work->list);
157 put_work(work);
158 }
159 return 0;
160}
161
162/*
163 * Save private data from incoming connection requests to
164 * iw_cm_event, so the low level driver doesn't have to. Adjust
165 * the event ptr to point to the local copy.
166 */
167static int copy_private_data(struct iw_cm_event *event)
168{
169 void *p;
170
171 p = kmemdup(event->private_data, event->private_data_len, GFP_ATOMIC);
172 if (!p)
173 return -ENOMEM;
174 event->private_data = p;
175 return 0;
176}
177
178static void free_cm_id(struct iwcm_id_private *cm_id_priv)
179{
180 dealloc_work_entries(cm_id_priv);
181 kfree(cm_id_priv);
182}
183
184/*
185 * Release a reference on cm_id. If the last reference is being
186 * released, enable the waiting thread (in iw_destroy_cm_id) to
187 * get woken up, and return 1 if a thread is already waiting.
188 */
189static int iwcm_deref_id(struct iwcm_id_private *cm_id_priv)
190{
191 BUG_ON(atomic_read(&cm_id_priv->refcount)==0);
192 if (atomic_dec_and_test(&cm_id_priv->refcount)) {
193 BUG_ON(!list_empty(&cm_id_priv->work_list));
194 complete(&cm_id_priv->destroy_comp);
195 return 1;
196 }
197
198 return 0;
199}
200
201static void add_ref(struct iw_cm_id *cm_id)
202{
203 struct iwcm_id_private *cm_id_priv;
204 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
205 atomic_inc(&cm_id_priv->refcount);
206}
207
208static void rem_ref(struct iw_cm_id *cm_id)
209{
210 struct iwcm_id_private *cm_id_priv;
211 int cb_destroy;
212
213 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
214
215 /*
216 * Test bit before deref in case the cm_id gets freed on another
217 * thread.
218 */
219 cb_destroy = test_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags);
220 if (iwcm_deref_id(cm_id_priv) && cb_destroy) {
221 BUG_ON(!list_empty(&cm_id_priv->work_list));
222 free_cm_id(cm_id_priv);
223 }
224}
225
226static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *event);
227
228struct iw_cm_id *iw_create_cm_id(struct ib_device *device,
229 iw_cm_handler cm_handler,
230 void *context)
231{
232 struct iwcm_id_private *cm_id_priv;
233
234 cm_id_priv = kzalloc(sizeof(*cm_id_priv), GFP_KERNEL);
235 if (!cm_id_priv)
236 return ERR_PTR(-ENOMEM);
237
238 cm_id_priv->state = IW_CM_STATE_IDLE;
239 cm_id_priv->id.device = device;
240 cm_id_priv->id.cm_handler = cm_handler;
241 cm_id_priv->id.context = context;
242 cm_id_priv->id.event_handler = cm_event_handler;
243 cm_id_priv->id.add_ref = add_ref;
244 cm_id_priv->id.rem_ref = rem_ref;
245 spin_lock_init(&cm_id_priv->lock);
246 atomic_set(&cm_id_priv->refcount, 1);
247 init_waitqueue_head(&cm_id_priv->connect_wait);
248 init_completion(&cm_id_priv->destroy_comp);
249 INIT_LIST_HEAD(&cm_id_priv->work_list);
250 INIT_LIST_HEAD(&cm_id_priv->work_free_list);
251
252 return &cm_id_priv->id;
253}
254EXPORT_SYMBOL(iw_create_cm_id);
255
256
257static int iwcm_modify_qp_err(struct ib_qp *qp)
258{
259 struct ib_qp_attr qp_attr;
260
261 if (!qp)
262 return -EINVAL;
263
264 qp_attr.qp_state = IB_QPS_ERR;
265 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
266}
267
268/*
269 * This is really the RDMAC CLOSING state. It is most similar to the
270 * IB SQD QP state.
271 */
272static int iwcm_modify_qp_sqd(struct ib_qp *qp)
273{
274 struct ib_qp_attr qp_attr;
275
276 BUG_ON(qp == NULL);
277 qp_attr.qp_state = IB_QPS_SQD;
278 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
279}
280
281/*
282 * CM_ID <-- CLOSING
283 *
284 * Block if a passive or active connection is currently being processed. Then
285 * process the event as follows:
286 * - If we are ESTABLISHED, move to CLOSING and modify the QP state
287 * based on the abrupt flag
288 * - If the connection is already in the CLOSING or IDLE state, the peer is
289 * disconnecting concurrently with us and we've already seen the
290 * DISCONNECT event -- ignore the request and return 0
291 * - Disconnect on a listening endpoint returns -EINVAL
292 */
293int iw_cm_disconnect(struct iw_cm_id *cm_id, int abrupt)
294{
295 struct iwcm_id_private *cm_id_priv;
296 unsigned long flags;
297 int ret = 0;
298 struct ib_qp *qp = NULL;
299
300 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
301 /* Wait if we're currently in a connect or accept downcall */
302 wait_event(cm_id_priv->connect_wait,
303 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
304
305 spin_lock_irqsave(&cm_id_priv->lock, flags);
306 switch (cm_id_priv->state) {
307 case IW_CM_STATE_ESTABLISHED:
308 cm_id_priv->state = IW_CM_STATE_CLOSING;
309
310 /* QP could be <nul> for user-mode client */
311 if (cm_id_priv->qp)
312 qp = cm_id_priv->qp;
313 else
314 ret = -EINVAL;
315 break;
316 case IW_CM_STATE_LISTEN:
317 ret = -EINVAL;
318 break;
319 case IW_CM_STATE_CLOSING:
320 /* remote peer closed first */
321 case IW_CM_STATE_IDLE:
322 /* accept or connect returned !0 */
323 break;
324 case IW_CM_STATE_CONN_RECV:
325 /*
326 * App called disconnect before/without calling accept after
327 * connect_request event delivered.
328 */
329 break;
330 case IW_CM_STATE_CONN_SENT:
331 /* Can only get here if wait above fails */
332 default:
333 BUG();
334 }
335 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
336
337 if (qp) {
338 if (abrupt)
339 ret = iwcm_modify_qp_err(qp);
340 else
341 ret = iwcm_modify_qp_sqd(qp);
342
343 /*
344 * If both sides are disconnecting the QP could
345 * already be in ERR or SQD states
346 */
347 ret = 0;
348 }
349
350 return ret;
351}
352EXPORT_SYMBOL(iw_cm_disconnect);
353
354/*
355 * CM_ID <-- DESTROYING
356 *
357 * Clean up all resources associated with the connection and release
358 * the initial reference taken by iw_create_cm_id.
359 */
360static void destroy_cm_id(struct iw_cm_id *cm_id)
361{
362 struct iwcm_id_private *cm_id_priv;
363 unsigned long flags;
364
365 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
366 /*
367 * Wait if we're currently in a connect or accept downcall. A
368 * listening endpoint should never block here.
369 */
370 wait_event(cm_id_priv->connect_wait,
371 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
372
373 spin_lock_irqsave(&cm_id_priv->lock, flags);
374 switch (cm_id_priv->state) {
375 case IW_CM_STATE_LISTEN:
376 cm_id_priv->state = IW_CM_STATE_DESTROYING;
377 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
378 /* destroy the listening endpoint */
379 cm_id->device->iwcm->destroy_listen(cm_id);
380 spin_lock_irqsave(&cm_id_priv->lock, flags);
381 break;
382 case IW_CM_STATE_ESTABLISHED:
383 cm_id_priv->state = IW_CM_STATE_DESTROYING;
384 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
385 /* Abrupt close of the connection */
386 (void)iwcm_modify_qp_err(cm_id_priv->qp);
387 spin_lock_irqsave(&cm_id_priv->lock, flags);
388 break;
389 case IW_CM_STATE_IDLE:
390 case IW_CM_STATE_CLOSING:
391 cm_id_priv->state = IW_CM_STATE_DESTROYING;
392 break;
393 case IW_CM_STATE_CONN_RECV:
394 /*
395 * App called destroy before/without calling accept after
396 * receiving connection request event notification or
397 * returned non zero from the event callback function.
398 * In either case, must tell the provider to reject.
399 */
400 cm_id_priv->state = IW_CM_STATE_DESTROYING;
401 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
402 cm_id->device->iwcm->reject(cm_id, NULL, 0);
403 spin_lock_irqsave(&cm_id_priv->lock, flags);
404 break;
405 case IW_CM_STATE_CONN_SENT:
406 case IW_CM_STATE_DESTROYING:
407 default:
408 BUG();
409 break;
410 }
411 if (cm_id_priv->qp) {
412 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
413 cm_id_priv->qp = NULL;
414 }
415 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
416
417 if (cm_id->mapped) {
418 iwpm_remove_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr);
419 iwpm_remove_mapping(&cm_id->local_addr, RDMA_NL_IWCM);
420 }
421
422 (void)iwcm_deref_id(cm_id_priv);
423}
424
425/*
426 * This function is only called by the application thread and cannot
427 * be called by the event thread. The function will wait for all
428 * references to be released on the cm_id and then kfree the cm_id
429 * object.
430 */
431void iw_destroy_cm_id(struct iw_cm_id *cm_id)
432{
433 struct iwcm_id_private *cm_id_priv;
434
435 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
436 BUG_ON(test_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags));
437
438 destroy_cm_id(cm_id);
439
440 wait_for_completion(&cm_id_priv->destroy_comp);
441
442 free_cm_id(cm_id_priv);
443}
444EXPORT_SYMBOL(iw_destroy_cm_id);
445
446/**
447 * iw_cm_check_wildcard - If IP address is 0 then use original
448 * @pm_addr: sockaddr containing the ip to check for wildcard
449 * @cm_addr: sockaddr containing the actual IP address
450 * @cm_outaddr: sockaddr to set IP addr which leaving port
451 *
452 * Checks the pm_addr for wildcard and then sets cm_outaddr's
453 * IP to the actual (cm_addr).
454 */
455static void iw_cm_check_wildcard(struct sockaddr_storage *pm_addr,
456 struct sockaddr_storage *cm_addr,
457 struct sockaddr_storage *cm_outaddr)
458{
459 if (pm_addr->ss_family == AF_INET) {
460 struct sockaddr_in *pm4_addr = (struct sockaddr_in *)pm_addr;
461
462 if (pm4_addr->sin_addr.s_addr == INADDR_ANY) {
463 struct sockaddr_in *cm4_addr =
464 (struct sockaddr_in *)cm_addr;
465 struct sockaddr_in *cm4_outaddr =
466 (struct sockaddr_in *)cm_outaddr;
467
468 cm4_outaddr->sin_addr = cm4_addr->sin_addr;
469 }
470 } else {
471 struct sockaddr_in6 *pm6_addr = (struct sockaddr_in6 *)pm_addr;
472
473 if (ipv6_addr_type(&pm6_addr->sin6_addr) == IPV6_ADDR_ANY) {
474 struct sockaddr_in6 *cm6_addr =
475 (struct sockaddr_in6 *)cm_addr;
476 struct sockaddr_in6 *cm6_outaddr =
477 (struct sockaddr_in6 *)cm_outaddr;
478
479 cm6_outaddr->sin6_addr = cm6_addr->sin6_addr;
480 }
481 }
482}
483
484/**
485 * iw_cm_map - Use portmapper to map the ports
486 * @cm_id: connection manager pointer
487 * @active: Indicates the active side when true
488 * returns nonzero for error only if iwpm_create_mapinfo() fails
489 *
490 * Tries to add a mapping for a port using the Portmapper. If
491 * successful in mapping the IP/Port it will check the remote
492 * mapped IP address for a wildcard IP address and replace the
493 * zero IP address with the remote_addr.
494 */
495static int iw_cm_map(struct iw_cm_id *cm_id, bool active)
496{
497 struct iwpm_dev_data pm_reg_msg;
498 struct iwpm_sa_data pm_msg;
499 int status;
500
501 cm_id->m_local_addr = cm_id->local_addr;
502 cm_id->m_remote_addr = cm_id->remote_addr;
503
504 memcpy(pm_reg_msg.dev_name, cm_id->device->name,
505 sizeof(pm_reg_msg.dev_name));
506 memcpy(pm_reg_msg.if_name, cm_id->device->iwcm->ifname,
507 sizeof(pm_reg_msg.if_name));
508
509 if (iwpm_register_pid(&pm_reg_msg, RDMA_NL_IWCM) ||
510 !iwpm_valid_pid())
511 return 0;
512
513 cm_id->mapped = true;
514 pm_msg.loc_addr = cm_id->local_addr;
515 pm_msg.rem_addr = cm_id->remote_addr;
516 if (active)
517 status = iwpm_add_and_query_mapping(&pm_msg,
518 RDMA_NL_IWCM);
519 else
520 status = iwpm_add_mapping(&pm_msg, RDMA_NL_IWCM);
521
522 if (!status) {
523 cm_id->m_local_addr = pm_msg.mapped_loc_addr;
524 if (active) {
525 cm_id->m_remote_addr = pm_msg.mapped_rem_addr;
526 iw_cm_check_wildcard(&pm_msg.mapped_rem_addr,
527 &cm_id->remote_addr,
528 &cm_id->m_remote_addr);
529 }
530 }
531
532 return iwpm_create_mapinfo(&cm_id->local_addr,
533 &cm_id->m_local_addr,
534 RDMA_NL_IWCM);
535}
536
537/*
538 * CM_ID <-- LISTEN
539 *
540 * Start listening for connect requests. Generates one CONNECT_REQUEST
541 * event for each inbound connect request.
542 */
543int iw_cm_listen(struct iw_cm_id *cm_id, int backlog)
544{
545 struct iwcm_id_private *cm_id_priv;
546 unsigned long flags;
547 int ret;
548
549 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
550
551 if (!backlog)
552 backlog = default_backlog;
553
554 ret = alloc_work_entries(cm_id_priv, backlog);
555 if (ret)
556 return ret;
557
558 spin_lock_irqsave(&cm_id_priv->lock, flags);
559 switch (cm_id_priv->state) {
560 case IW_CM_STATE_IDLE:
561 cm_id_priv->state = IW_CM_STATE_LISTEN;
562 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
563 ret = iw_cm_map(cm_id, false);
564 if (!ret)
565 ret = cm_id->device->iwcm->create_listen(cm_id, backlog);
566 if (ret)
567 cm_id_priv->state = IW_CM_STATE_IDLE;
568 spin_lock_irqsave(&cm_id_priv->lock, flags);
569 break;
570 default:
571 ret = -EINVAL;
572 }
573 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
574
575 return ret;
576}
577EXPORT_SYMBOL(iw_cm_listen);
578
579/*
580 * CM_ID <-- IDLE
581 *
582 * Rejects an inbound connection request. No events are generated.
583 */
584int iw_cm_reject(struct iw_cm_id *cm_id,
585 const void *private_data,
586 u8 private_data_len)
587{
588 struct iwcm_id_private *cm_id_priv;
589 unsigned long flags;
590 int ret;
591
592 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
593 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
594
595 spin_lock_irqsave(&cm_id_priv->lock, flags);
596 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
597 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
598 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
599 wake_up_all(&cm_id_priv->connect_wait);
600 return -EINVAL;
601 }
602 cm_id_priv->state = IW_CM_STATE_IDLE;
603 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
604
605 ret = cm_id->device->iwcm->reject(cm_id, private_data,
606 private_data_len);
607
608 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
609 wake_up_all(&cm_id_priv->connect_wait);
610
611 return ret;
612}
613EXPORT_SYMBOL(iw_cm_reject);
614
615/*
616 * CM_ID <-- ESTABLISHED
617 *
618 * Accepts an inbound connection request and generates an ESTABLISHED
619 * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block
620 * until the ESTABLISHED event is received from the provider.
621 */
622int iw_cm_accept(struct iw_cm_id *cm_id,
623 struct iw_cm_conn_param *iw_param)
624{
625 struct iwcm_id_private *cm_id_priv;
626 struct ib_qp *qp;
627 unsigned long flags;
628 int ret;
629
630 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
631 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
632
633 spin_lock_irqsave(&cm_id_priv->lock, flags);
634 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
635 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
636 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
637 wake_up_all(&cm_id_priv->connect_wait);
638 return -EINVAL;
639 }
640 /* Get the ib_qp given the QPN */
641 qp = cm_id->device->iwcm->get_qp(cm_id->device, iw_param->qpn);
642 if (!qp) {
643 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
644 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
645 wake_up_all(&cm_id_priv->connect_wait);
646 return -EINVAL;
647 }
648 cm_id->device->iwcm->add_ref(qp);
649 cm_id_priv->qp = qp;
650 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
651
652 ret = cm_id->device->iwcm->accept(cm_id, iw_param);
653 if (ret) {
654 /* An error on accept precludes provider events */
655 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
656 cm_id_priv->state = IW_CM_STATE_IDLE;
657 spin_lock_irqsave(&cm_id_priv->lock, flags);
658 if (cm_id_priv->qp) {
659 cm_id->device->iwcm->rem_ref(qp);
660 cm_id_priv->qp = NULL;
661 }
662 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
663 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
664 wake_up_all(&cm_id_priv->connect_wait);
665 }
666
667 return ret;
668}
669EXPORT_SYMBOL(iw_cm_accept);
670
671/*
672 * Active Side: CM_ID <-- CONN_SENT
673 *
674 * If successful, results in the generation of a CONNECT_REPLY
675 * event. iw_cm_disconnect and iw_cm_destroy will block until the
676 * CONNECT_REPLY event is received from the provider.
677 */
678int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param)
679{
680 struct iwcm_id_private *cm_id_priv;
681 int ret;
682 unsigned long flags;
683 struct ib_qp *qp;
684
685 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
686
687 ret = alloc_work_entries(cm_id_priv, 4);
688 if (ret)
689 return ret;
690
691 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
692 spin_lock_irqsave(&cm_id_priv->lock, flags);
693
694 if (cm_id_priv->state != IW_CM_STATE_IDLE) {
695 ret = -EINVAL;
696 goto err;
697 }
698
699 /* Get the ib_qp given the QPN */
700 qp = cm_id->device->iwcm->get_qp(cm_id->device, iw_param->qpn);
701 if (!qp) {
702 ret = -EINVAL;
703 goto err;
704 }
705 cm_id->device->iwcm->add_ref(qp);
706 cm_id_priv->qp = qp;
707 cm_id_priv->state = IW_CM_STATE_CONN_SENT;
708 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
709
710 ret = iw_cm_map(cm_id, true);
711 if (!ret)
712 ret = cm_id->device->iwcm->connect(cm_id, iw_param);
713 if (!ret)
714 return 0; /* success */
715
716 spin_lock_irqsave(&cm_id_priv->lock, flags);
717 if (cm_id_priv->qp) {
718 cm_id->device->iwcm->rem_ref(qp);
719 cm_id_priv->qp = NULL;
720 }
721 cm_id_priv->state = IW_CM_STATE_IDLE;
722err:
723 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
724 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
725 wake_up_all(&cm_id_priv->connect_wait);
726 return ret;
727}
728EXPORT_SYMBOL(iw_cm_connect);
729
730/*
731 * Passive Side: new CM_ID <-- CONN_RECV
732 *
733 * Handles an inbound connect request. The function creates a new
734 * iw_cm_id to represent the new connection and inherits the client
735 * callback function and other attributes from the listening parent.
736 *
737 * The work item contains a pointer to the listen_cm_id and the event. The
738 * listen_cm_id contains the client cm_handler, context and
739 * device. These are copied when the device is cloned. The event
740 * contains the new four tuple.
741 *
742 * An error on the child should not affect the parent, so this
743 * function does not return a value.
744 */
745static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv,
746 struct iw_cm_event *iw_event)
747{
748 unsigned long flags;
749 struct iw_cm_id *cm_id;
750 struct iwcm_id_private *cm_id_priv;
751 int ret;
752
753 /*
754 * The provider should never generate a connection request
755 * event with a bad status.
756 */
757 BUG_ON(iw_event->status);
758
759 cm_id = iw_create_cm_id(listen_id_priv->id.device,
760 listen_id_priv->id.cm_handler,
761 listen_id_priv->id.context);
762 /* If the cm_id could not be created, ignore the request */
763 if (IS_ERR(cm_id))
764 goto out;
765
766 cm_id->provider_data = iw_event->provider_data;
767 cm_id->m_local_addr = iw_event->local_addr;
768 cm_id->m_remote_addr = iw_event->remote_addr;
769 cm_id->local_addr = listen_id_priv->id.local_addr;
770
771 ret = iwpm_get_remote_info(&listen_id_priv->id.m_local_addr,
772 &iw_event->remote_addr,
773 &cm_id->remote_addr,
774 RDMA_NL_IWCM);
775 if (ret) {
776 cm_id->remote_addr = iw_event->remote_addr;
777 } else {
778 iw_cm_check_wildcard(&listen_id_priv->id.m_local_addr,
779 &iw_event->local_addr,
780 &cm_id->local_addr);
781 iw_event->local_addr = cm_id->local_addr;
782 iw_event->remote_addr = cm_id->remote_addr;
783 }
784
785 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
786 cm_id_priv->state = IW_CM_STATE_CONN_RECV;
787
788 /*
789 * We could be destroying the listening id. If so, ignore this
790 * upcall.
791 */
792 spin_lock_irqsave(&listen_id_priv->lock, flags);
793 if (listen_id_priv->state != IW_CM_STATE_LISTEN) {
794 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
795 iw_cm_reject(cm_id, NULL, 0);
796 iw_destroy_cm_id(cm_id);
797 goto out;
798 }
799 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
800
801 ret = alloc_work_entries(cm_id_priv, 3);
802 if (ret) {
803 iw_cm_reject(cm_id, NULL, 0);
804 iw_destroy_cm_id(cm_id);
805 goto out;
806 }
807
808 /* Call the client CM handler */
809 ret = cm_id->cm_handler(cm_id, iw_event);
810 if (ret) {
811 iw_cm_reject(cm_id, NULL, 0);
812 set_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags);
813 destroy_cm_id(cm_id);
814 if (atomic_read(&cm_id_priv->refcount)==0)
815 free_cm_id(cm_id_priv);
816 }
817
818out:
819 if (iw_event->private_data_len)
820 kfree(iw_event->private_data);
821}
822
823/*
824 * Passive Side: CM_ID <-- ESTABLISHED
825 *
826 * The provider generated an ESTABLISHED event which means that
827 * the MPA negotion has completed successfully and we are now in MPA
828 * FPDU mode.
829 *
830 * This event can only be received in the CONN_RECV state. If the
831 * remote peer closed, the ESTABLISHED event would be received followed
832 * by the CLOSE event. If the app closes, it will block until we wake
833 * it up after processing this event.
834 */
835static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv,
836 struct iw_cm_event *iw_event)
837{
838 unsigned long flags;
839 int ret;
840
841 spin_lock_irqsave(&cm_id_priv->lock, flags);
842
843 /*
844 * We clear the CONNECT_WAIT bit here to allow the callback
845 * function to call iw_cm_disconnect. Calling iw_destroy_cm_id
846 * from a callback handler is not allowed.
847 */
848 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
849 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
850 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
851 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
852 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
853 wake_up_all(&cm_id_priv->connect_wait);
854
855 return ret;
856}
857
858/*
859 * Active Side: CM_ID <-- ESTABLISHED
860 *
861 * The app has called connect and is waiting for the established event to
862 * post it's requests to the server. This event will wake up anyone
863 * blocked in iw_cm_disconnect or iw_destroy_id.
864 */
865static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv,
866 struct iw_cm_event *iw_event)
867{
868 unsigned long flags;
869 int ret;
870
871 spin_lock_irqsave(&cm_id_priv->lock, flags);
872 /*
873 * Clear the connect wait bit so a callback function calling
874 * iw_cm_disconnect will not wait and deadlock this thread
875 */
876 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
877 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT);
878 if (iw_event->status == 0) {
879 cm_id_priv->id.m_local_addr = iw_event->local_addr;
880 cm_id_priv->id.m_remote_addr = iw_event->remote_addr;
881 iw_event->local_addr = cm_id_priv->id.local_addr;
882 iw_event->remote_addr = cm_id_priv->id.remote_addr;
883 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
884 } else {
885 /* REJECTED or RESET */
886 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
887 cm_id_priv->qp = NULL;
888 cm_id_priv->state = IW_CM_STATE_IDLE;
889 }
890 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
891 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
892
893 if (iw_event->private_data_len)
894 kfree(iw_event->private_data);
895
896 /* Wake up waiters on connect complete */
897 wake_up_all(&cm_id_priv->connect_wait);
898
899 return ret;
900}
901
902/*
903 * CM_ID <-- CLOSING
904 *
905 * If in the ESTABLISHED state, move to CLOSING.
906 */
907static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv,
908 struct iw_cm_event *iw_event)
909{
910 unsigned long flags;
911
912 spin_lock_irqsave(&cm_id_priv->lock, flags);
913 if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED)
914 cm_id_priv->state = IW_CM_STATE_CLOSING;
915 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
916}
917
918/*
919 * CM_ID <-- IDLE
920 *
921 * If in the ESTBLISHED or CLOSING states, the QP will have have been
922 * moved by the provider to the ERR state. Disassociate the CM_ID from
923 * the QP, move to IDLE, and remove the 'connected' reference.
924 *
925 * If in some other state, the cm_id was destroyed asynchronously.
926 * This is the last reference that will result in waking up
927 * the app thread blocked in iw_destroy_cm_id.
928 */
929static int cm_close_handler(struct iwcm_id_private *cm_id_priv,
930 struct iw_cm_event *iw_event)
931{
932 unsigned long flags;
933 int ret = 0;
934 spin_lock_irqsave(&cm_id_priv->lock, flags);
935
936 if (cm_id_priv->qp) {
937 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
938 cm_id_priv->qp = NULL;
939 }
940 switch (cm_id_priv->state) {
941 case IW_CM_STATE_ESTABLISHED:
942 case IW_CM_STATE_CLOSING:
943 cm_id_priv->state = IW_CM_STATE_IDLE;
944 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
945 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
946 spin_lock_irqsave(&cm_id_priv->lock, flags);
947 break;
948 case IW_CM_STATE_DESTROYING:
949 break;
950 default:
951 BUG();
952 }
953 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
954
955 return ret;
956}
957
958static int process_event(struct iwcm_id_private *cm_id_priv,
959 struct iw_cm_event *iw_event)
960{
961 int ret = 0;
962
963 switch (iw_event->event) {
964 case IW_CM_EVENT_CONNECT_REQUEST:
965 cm_conn_req_handler(cm_id_priv, iw_event);
966 break;
967 case IW_CM_EVENT_CONNECT_REPLY:
968 ret = cm_conn_rep_handler(cm_id_priv, iw_event);
969 break;
970 case IW_CM_EVENT_ESTABLISHED:
971 ret = cm_conn_est_handler(cm_id_priv, iw_event);
972 break;
973 case IW_CM_EVENT_DISCONNECT:
974 cm_disconnect_handler(cm_id_priv, iw_event);
975 break;
976 case IW_CM_EVENT_CLOSE:
977 ret = cm_close_handler(cm_id_priv, iw_event);
978 break;
979 default:
980 BUG();
981 }
982
983 return ret;
984}
985
986/*
987 * Process events on the work_list for the cm_id. If the callback
988 * function requests that the cm_id be deleted, a flag is set in the
989 * cm_id flags to indicate that when the last reference is
990 * removed, the cm_id is to be destroyed. This is necessary to
991 * distinguish between an object that will be destroyed by the app
992 * thread asleep on the destroy_comp list vs. an object destroyed
993 * here synchronously when the last reference is removed.
994 */
995static void cm_work_handler(struct work_struct *_work)
996{
997 struct iwcm_work *work = container_of(_work, struct iwcm_work, work);
998 struct iw_cm_event levent;
999 struct iwcm_id_private *cm_id_priv = work->cm_id;
1000 unsigned long flags;
1001 int empty;
1002 int ret = 0;
1003 int destroy_id;
1004
1005 spin_lock_irqsave(&cm_id_priv->lock, flags);
1006 empty = list_empty(&cm_id_priv->work_list);
1007 while (!empty) {
1008 work = list_entry(cm_id_priv->work_list.next,
1009 struct iwcm_work, list);
1010 list_del_init(&work->list);
1011 empty = list_empty(&cm_id_priv->work_list);
1012 levent = work->event;
1013 put_work(work);
1014 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1015
1016 ret = process_event(cm_id_priv, &levent);
1017 if (ret) {
1018 set_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags);
1019 destroy_cm_id(&cm_id_priv->id);
1020 }
1021 BUG_ON(atomic_read(&cm_id_priv->refcount)==0);
1022 destroy_id = test_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags);
1023 if (iwcm_deref_id(cm_id_priv)) {
1024 if (destroy_id) {
1025 BUG_ON(!list_empty(&cm_id_priv->work_list));
1026 free_cm_id(cm_id_priv);
1027 }
1028 return;
1029 }
1030 if (empty)
1031 return;
1032 spin_lock_irqsave(&cm_id_priv->lock, flags);
1033 }
1034 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1035}
1036
1037/*
1038 * This function is called on interrupt context. Schedule events on
1039 * the iwcm_wq thread to allow callback functions to downcall into
1040 * the CM and/or block. Events are queued to a per-CM_ID
1041 * work_list. If this is the first event on the work_list, the work
1042 * element is also queued on the iwcm_wq thread.
1043 *
1044 * Each event holds a reference on the cm_id. Until the last posted
1045 * event has been delivered and processed, the cm_id cannot be
1046 * deleted.
1047 *
1048 * Returns:
1049 * 0 - the event was handled.
1050 * -ENOMEM - the event was not handled due to lack of resources.
1051 */
1052static int cm_event_handler(struct iw_cm_id *cm_id,
1053 struct iw_cm_event *iw_event)
1054{
1055 struct iwcm_work *work;
1056 struct iwcm_id_private *cm_id_priv;
1057 unsigned long flags;
1058 int ret = 0;
1059
1060 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
1061
1062 spin_lock_irqsave(&cm_id_priv->lock, flags);
1063 work = get_work(cm_id_priv);
1064 if (!work) {
1065 ret = -ENOMEM;
1066 goto out;
1067 }
1068
1069 INIT_WORK(&work->work, cm_work_handler);
1070 work->cm_id = cm_id_priv;
1071 work->event = *iw_event;
1072
1073 if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST ||
1074 work->event.event == IW_CM_EVENT_CONNECT_REPLY) &&
1075 work->event.private_data_len) {
1076 ret = copy_private_data(&work->event);
1077 if (ret) {
1078 put_work(work);
1079 goto out;
1080 }
1081 }
1082
1083 atomic_inc(&cm_id_priv->refcount);
1084 if (list_empty(&cm_id_priv->work_list)) {
1085 list_add_tail(&work->list, &cm_id_priv->work_list);
1086 queue_work(iwcm_wq, &work->work);
1087 } else
1088 list_add_tail(&work->list, &cm_id_priv->work_list);
1089out:
1090 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1091 return ret;
1092}
1093
1094static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv,
1095 struct ib_qp_attr *qp_attr,
1096 int *qp_attr_mask)
1097{
1098 unsigned long flags;
1099 int ret;
1100
1101 spin_lock_irqsave(&cm_id_priv->lock, flags);
1102 switch (cm_id_priv->state) {
1103 case IW_CM_STATE_IDLE:
1104 case IW_CM_STATE_CONN_SENT:
1105 case IW_CM_STATE_CONN_RECV:
1106 case IW_CM_STATE_ESTABLISHED:
1107 *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS;
1108 qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE|
1109 IB_ACCESS_REMOTE_READ;
1110 ret = 0;
1111 break;
1112 default:
1113 ret = -EINVAL;
1114 break;
1115 }
1116 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1117 return ret;
1118}
1119
1120static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv,
1121 struct ib_qp_attr *qp_attr,
1122 int *qp_attr_mask)
1123{
1124 unsigned long flags;
1125 int ret;
1126
1127 spin_lock_irqsave(&cm_id_priv->lock, flags);
1128 switch (cm_id_priv->state) {
1129 case IW_CM_STATE_IDLE:
1130 case IW_CM_STATE_CONN_SENT:
1131 case IW_CM_STATE_CONN_RECV:
1132 case IW_CM_STATE_ESTABLISHED:
1133 *qp_attr_mask = 0;
1134 ret = 0;
1135 break;
1136 default:
1137 ret = -EINVAL;
1138 break;
1139 }
1140 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1141 return ret;
1142}
1143
1144int iw_cm_init_qp_attr(struct iw_cm_id *cm_id,
1145 struct ib_qp_attr *qp_attr,
1146 int *qp_attr_mask)
1147{
1148 struct iwcm_id_private *cm_id_priv;
1149 int ret;
1150
1151 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
1152 switch (qp_attr->qp_state) {
1153 case IB_QPS_INIT:
1154 case IB_QPS_RTR:
1155 ret = iwcm_init_qp_init_attr(cm_id_priv,
1156 qp_attr, qp_attr_mask);
1157 break;
1158 case IB_QPS_RTS:
1159 ret = iwcm_init_qp_rts_attr(cm_id_priv,
1160 qp_attr, qp_attr_mask);
1161 break;
1162 default:
1163 ret = -EINVAL;
1164 break;
1165 }
1166 return ret;
1167}
1168EXPORT_SYMBOL(iw_cm_init_qp_attr);
1169
1170static int __init iw_cm_init(void)
1171{
1172 int ret;
1173
1174 ret = iwpm_init(RDMA_NL_IWCM);
1175 if (ret)
1176 pr_err("iw_cm: couldn't init iwpm\n");
1177
1178 ret = ibnl_add_client(RDMA_NL_IWCM, RDMA_NL_IWPM_NUM_OPS,
1179 iwcm_nl_cb_table);
1180 if (ret)
1181 pr_err("iw_cm: couldn't register netlink callbacks\n");
1182
1183 iwcm_wq = create_singlethread_workqueue("iw_cm_wq");
1184 if (!iwcm_wq)
1185 return -ENOMEM;
1186
1187 iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm",
1188 iwcm_ctl_table);
1189 if (!iwcm_ctl_table_hdr) {
1190 pr_err("iw_cm: couldn't register sysctl paths\n");
1191 destroy_workqueue(iwcm_wq);
1192 return -ENOMEM;
1193 }
1194
1195 return 0;
1196}
1197
1198static void __exit iw_cm_cleanup(void)
1199{
1200 unregister_net_sysctl_table(iwcm_ctl_table_hdr);
1201 destroy_workqueue(iwcm_wq);
1202 ibnl_remove_client(RDMA_NL_IWCM);
1203 iwpm_exit(RDMA_NL_IWCM);
1204}
1205
1206module_init(iw_cm_init);
1207module_exit(iw_cm_cleanup);